1 Health and Disease of the Cardiovascular system DR CHRIS MOORE Instructions 2 USE THE ARROWS TO NAVIGATE, OR TAP OUTLINE AT THE TOP TO BRING DOWN A SLIDE MENU Click these where you see them to zoom or start a closer look Click these where you see them to listen to an audio clip Click buttons like these where you see them to answer questions or get additional information. If a button turns green, click it again 1
Overview of Cardiovascular System 3 Simplified View Cardiac anatomy 4 2
Posterior aspect What aspect of the heart is this? 5 Superior Vena Cava Aortic arch Pulmonary artery Left pulmonary veins Right pulmonary veins Coronary sinus Left ventricle Valves 6 Pulmonary valve Aortic valve Tricuspid valve Mitral valve 3
Electrical activity 7 Venous and Arterial structure 8 4
CVS Pathologies 9 Angina Hypoglycaemia Atherosclerosis Diabetes Cardiac Arrhthymia Obesity Cardiac myopathy Sickle cell anaemia High Blood pressure High cholesterol Leukaemia High triglycerides Mitral Valve prolapse Hyperhomocystinaemia Most common cause? 10 Major classes of lipid Triglycerides Fatty acids Cholesterol Which category of lipid is this? Triglyceride 5
Fatty acids 11 Unsaturated and Saturated 12 It s all about the H More hydrogen added to structure, more conversion of double C- bonds to single One or many? The double bonds are known as having been saturated by hydrogen Monounsaturated Hydrogen taking up spaces One in double the chain C-bond instead of additional bonds makes the chain more Polyunsaturated tightly packed Multiple double C-bonds 6
Cis and Trans geometric isomerisms 13 Forms of stereo isomerisms Form of orientation in What? space Cis Trans Affects interaction at membrane Cholesterol the animal fat 14 Necessary for membrane maintenance/integrity and permeability Is amphipathic (hydrophilic and phobic) Hydroxyl group Steroid ring Hydrocarbon tail 7
To Bloodstream 26/01/2016 Absorption and digestion of lipids - Micelles 15 Transported in blood as Chylomicrons, lipoproteins, free fatty acids Chylomicrons fat droplets in blood soon after fat absorption Triglycerides + cholesterol and phospholipids Absorptive state lots of chylomicrons Postabsorptive state mostly absorbed into adipose tissue 95% of lipids remaining in blood now transported by lipoproteins Products of lipase action are lipid soluble Pass through plasma membrane of intestine and into epithelials Required for further breakdown and absorption in small intestine Hydrophobic end of bile salts absorbed into fat droplet Hydrophilic end sticks out of droplet Stops aggregation of fats to ease breakdown Overview of absorption 16 8
Transport of Cholesterol 17 The job of lipoproteins 5 major groups - chylomicron, VLDL, IDL, LDL, and HDL (lg to sm) Taken to liver via bloodstream as chylomicrons Packaged into other forms of lipoprotein Two routes To cells of body transport through surface Retrieved from tissues and returned to liver Good Vs Bad: HDL and LDL 18 LDL package works with receptors on cells to transport cholesterol inside Cholesterol then converted to steroids or energy source HDL returns cholesterol to liver Converted to useful material or mixed with bile and discarded into intestine as waste 9
19 CVS Diseases Atherosclerosis 20 Characterised by an accumulation of plaques of fatty material on the inner walls of arteries 10
Foam cell formation 21 Atherosclerosis therefore an inflammatory disease 22 Damage Risk factors roughen/damage inner layer of smooth epithelium LDL-C break-in LDL-C is able to pass through and into wall of artery Inflammatory response Macrophages move in to clean up LDL-C Macrophages become foam cells Enlarged, cholesterol rich cells take up space Fatty streak Fibrous capsule surrounds developing foam cells becomes plaque Click to toggle stages 11
Getting out of hand 23 Calcium deposited Pressure increases Elasticity reaches peak Fibrous capsule ruptures Clot forms Blocks vessel Implications and related diseases 24 Weakening of artery wall causing bulge Aneurysm if ruptures, haemorrhage and possible death Stroke or Heart attack Determined by location of thrombus Disease classified by location of plaque build up Coronary Heart Disease Carotid Artery Disease Peripheral Arterial Disease Chronic Kidney Disease 12
Arterio and Arteriolosclerosis 25 Thickening and hardening of the arterial walls without an implied cause Results in reduction in internal diameter of artery Thereby reducing amount of blood flowing through Some loss of elasticity Think of effects on pulse pressure wave Often a consequence of systemic hypertension or diabetes mellitus Angina 26 Chest pain due to ischaemia of heart muscle Blockage of coronary arteries Symptom of coronary heart disease (CHD) Two forms stable and unstable Stable- reduced blood flow that can be relieved Unstable blockage due to clot formation 13
Cardiomyopathy 27 Deterioration of heart muscle Usually extrinsic cause (outside the heart muscle) Ischaemia common cause 28 Cardiac Enzymes 14
Myocardial infarction 29 Heart muscle damage Another result of atherosclerosis Caused by blockage of coronary arteries Leads to death of cardiac cells in heart tissue nearby How do we assess this damage? 30 As cardiac muscle cells die, they release enzymes into the bloodstream Measurement of these in serum can predict either: Whether damage has occurred Likelihood of an MI occurring again Enzymes: Creatine Kinase (CK) and Troponin (T and I) 15
Myoglobin and Early Indicators 31 Found in cardiac and skeletal muscle Released more rapidly from infarcted cardiac muscle than CK and T Has high sensitivity but low specificity Useful as early detection/suspicion Prompts further tests 16